A measuring device includes a projector, a camera and a calculation device. The projector projects, on a target object, first stripe pattern light having a first period, second stripe pattern light having a second period, and third stripe pattern light having a third period. A relation of the periods is the first period<the second period<the third period. The camera captures an image of the first stripe pattern light, an image of the second stripe pattern light, and an image of the third stripe pattern light. The calculation device performs a phase analysis of luminance with a phase shifting method for the image of the first stripe pattern light, the image of the second stripe pattern light, and the image of the third stripe pattern light, and calculates a height of the target object based on obtained phase analysis results.
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5. The measuring device according to claim 3, wherein when the first period is defined as T1, the second period is defined as T2, and the third period is defined as T3, 2×T1<T2, T2<T3<1.5×T2.
6. The measuring device according to claim 3, wherein the processor is configured to determine the accuracy in calculation of the height of the target object between the high accuracy and the low accuracy based on the analysis result related to the captured image of the second stripe pattern light and the captured image of the third stripe pattern light.
7. The measuring device according to claim 3, wherein when the processor selects the low accuracy and calculates the height of the target object with using the second phase value and the third phase value and a calculated height of the target object is equal to or smaller than a height threshold, the calculation device is configured to select the high accuracy and calculate the height of the target object with using the first phase value, the second phase value, and the third phase value.
11. The measuring device according to claim 2, wherein when the first period is defined as T1, the second period is defined as T2, and the third period is defined as T3, 2×T1≤T2, T2<T3<1.5×T2.
12. The measuring device according to claim 2, wherein the processor is configured to determine the accuracy in calculation of the height of the target object between the high accuracy and the low accuracy based on the analysis result related to the captured image of the second stripe pattern light and the captured image of the third stripe pattern light.
13. The measuring device according to claim 2, wherein when the processor selects the low accuracy and calculates the height of the target object with using the second phase value and the third phase value and a calculated height of the target object is equal to or smaller than a height threshold, the calculation device is configured to select the high accuracy and calculate the height of the target object with using the first phase value, the second phase value, and the third phase value.
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April 16, 2020
July 9, 2024
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